[turbofan] Lower Smi field loads to Word32 field loads.

[turbofan] Lower Smi field loads to Word32 field loads.

If a Smi field load is truncated to Word32, we can just load the upper
32 bits on 64-bit architectures (with 32-bit Smis), which avoids the
nasty shift right that we'd have to perform otherwise to untag it.

R=jarin@chromium.org

Committed: https://crrev.com/71becab88d590bf3c3ebf3151a7425db9b6051c1
Cr-Commit-Position: refs/heads/master@{#37630}

[Benedikt Meurer, 2016-07-11 09:00:28]

The CQ bit was checked by bmeurer@chromium.org to run a CQ dry run

[commit-bot: I haz the power, 2016-07-11 09:00:32]

Dry run: CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[Benedikt Meurer, 2016-07-11 09:01:12]

Hey Jaro,

Here's another low hanging fruit for Kraken.
Please take a look.

Thanks,
Benedikt

[Jarin, 2016-07-11 09:11:29]

lgtm

[Benedikt Meurer, 2016-07-11 09:13:19]

The CQ bit was unchecked by bmeurer@chromium.org

[Benedikt Meurer, 2016-07-11 09:13:25]

The CQ bit was checked by bmeurer@chromium.org

[commit-bot: I haz the power, 2016-07-11 09:13:31]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2016-07-11 09:23:40]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2016-07-11 09:25:07]

Description was changed from

==========
[turbofan] Lower Smi field loads to Word32 field loads.

If a Smi field load is truncated to Word32, we can just load the upper
32 bits on 64-bit architectures (with 32-bit Smis), which avoids the
nasty shift right that we'd have to perform otherwise to untag it.

R=jarin@chromium.org
==========

to

==========
[turbofan] Lower Smi field loads to Word32 field loads.

If a Smi field load is truncated to Word32, we can just load the upper
32 bits on 64-bit architectures (with 32-bit Smis), which avoids the
nasty shift right that we'd have to perform otherwise to untag it.

R=jarin@chromium.org

Committed: https://crrev.com/71becab88d590bf3c3ebf3151a7425db9b6051c1
Cr-Commit-Position: refs/heads/master@{#37630}
==========

[commit-bot: I haz the power, 2016-07-11 09:25:11]

Patchset 1 (id:??) landed as
https://crrev.com/71becab88d590bf3c3ebf3151a7425db9b6051c1
Cr-Commit-Position: refs/heads/master@{#37630}